The word Polyethylene was probably first pronounced in a lecture which M. P. E. Berthelot delivered on April ,27, 1863 to the Chemical Society in Paris, reporting on the "polymerization" of various simple organic compounds (1). Much later this work appeared twice in the literature before the classical ICI breakthrough in the 1930's which is so colorfully described in Ballard's lecture. Once it came up at the end of the last century when H. von Pechmann obtained "a white flocculant material" from the decomposition of diazomethane which, one year later, was termed to be "polymethylene" - (CH )...